Answer: Length is 16 ft. Width is 5 feet.
Step-by-step explanation: Take the information given and write an equation. "Length decreased by 3 is 1" becomes L - 3w = 1 .
"Solve" for L. L= 3w +1
Write another equation for the formula of a perimeter. P=2L + 2w.
Substitute the values for L (from the first "solution" you wrote) and P (42 ft, given).
42 = 2(3w +1) + 2w. Solve this.
42= 6w +2 + 2w
42= 8w +2. Subtract 2 from both sides then divide both sides by 8.
W = 5
Substitute that into the first equation you wrote to get the Length.
L - 3(5) = 1
L -15 = 1. L = 1+15
L = 16
